The present invention relates to immunoprophylactic and immunotherapeutic agents comprising human interleukin 2 produced, e.g., by eucaryote cells including human lymphocytes, cloned human lymphocytes, transformed (malignant) human cell lines, and human T cell hybridomas and by procaryote cells possessing recombinant DNA against neoplastic dieases; bacterial, parasitic and viral infections; and immune disorder diseases such as immune deficiency and autoimmune diseases.